4.5 River Basins
urbanization (i.e., increased impervious surfaces, food plain development and flling, stream channel alterations) seem to be increasing throughout the basin, with some areas experiencing greater impacts than others. Habitat degradation from point sources of pollution, though not as widespread as nonpoint sources, is still a signifcant problem in portions of the basin. Compared to other basins in the region (e.g., Hiwassee, Little Tennessee, and Catawba), impacts from impoundments are relatively minor in the French Broad River Basin; however, these impacts are an issue for portions of the basin. Problems associated with nonnative and invasive species are unclear at present; how- ever, the native Long-Ear Sunfsh has apparently been displaced entirely throughout the basin by the nonnative Redbreast Sunfsh. Te White River Crayfsh, White Catfsh, Flat Bullhead and Snail Bullhead (all native to the Atlantic Slope) are established in the basin. Te Red Swamp Crawfsh, a native of the lower Mississippi and Gulf Coast drainages, has apparently become established recently in the upper French Broad River subbasin, and could threaten the endemic French Broad Crayfsh. Te Asian Clam is known to exist in the French Broad River subbasin, but its extent throughout the basin is not fully documented. Te invasive Japanese Knotweed is widespread and expanding in riparian areas through- out the basin. Habitat for priority aquatic species in the French Broad River subbasin is afected by impacts related to development and urbanization, agriculture, and point sources. Sedimentation and turbidity are more or less chronic problems in most of the larger streams in the lower elevations of the Asheville watershed and surrounding area, including the mainstem French Broad River. Point source pollution, including both present problems and residual efects from much more severe pollution of the past, contributes signifcantly to habitat degradation and the extirpation of priority species. However, aquatic habitats overall have improved substantially over the past 40 years. Very few high-quality habitats for cool- and warmwater priority species in medium to large streams have remained intact through the 20th century. Te mainstem French Broad River and tributaries from the confuence of the Davidson River downstream to the Tennessee border have lost a substantial portion of their aquatic species. Habitat continues to remain unsuitable for some of these species; however, recovery of some species may be possible. Te Upper French Broad River, Little River, Mills River, and Ivy River have been the pri- mary refuges for most of the priority species that are still extant in this subbasin. However, increased development and chance events are ever-present threats in such fragmented refugia.
High-quality habitat for priority mussels in the Little River is limited to a short reach between Cascade Lake and the confuence of Crab Creek, where sedimentation from
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2015 NC Wildlife Action Plan
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